Impact of Body Mass Index and the Metabolic Syndrome on the Risk of Cardiovascular Disease and Death in Middle-Aged Men

TLDR

BMI and metabolic syndrome are established risk factors for cardiovascular disease and mortality in middle‑aged men. This study sought to determine how combinations of BMI categories and metabolic syndrome influence cardiovascular disease and death risk in this population. Researchers evaluated 1,758 diabetes‑free men at age 50 in the Uppsala Longitudinal Study of Adult Men, categorizing them into six BMI‑MetS groups based on BMI and NCEP criteria. During a median 30‑year follow‑up, all BMI‑MetS groups—including overweight and obese men without metabolic syndrome—exhibited markedly higher risks of cardiovascular events and mortality compared with normal‑weight, non‑MetS men.

Abstract

Background— The purpose of this study was to investigate associations between combinations of body mass index (BMI) categories and metabolic syndrome (MetS) and the risk of cardiovascular disease and death in middle-aged men. Methods and Results— At age 50 years, cardiovascular risk factors were assessed in 1758 participants without diabetes in the community-based Uppsala Longitudinal Study of Adult Men (ULSAM). According to BMI-MetS status, they were categorized as normal weight (BMI <25 kg/m 2 ) without MetS (National Cholesterol Education Program criteria; n=891), normal weight with MetS (n=64), overweight (BMI 25 to 30 kg/m 2 ) without MetS (n=582), overweight with MetS (n=125), obese (BMI >30 kg/m 2 ) without MetS (n=30), or obese with MetS (n=66). During follow-up (median 30 years), 788 participants died, and 681 developed cardiovascular disease (composite of cardiovascular death or hospitalization for myocardial infarction, stroke, or heart failure). In Cox proportional-hazards models that adjusted for age, smoking, and low-density lipoprotein cholesterol, an increased risk for cardiovascular disease was observed in normal-weight participants with MetS (hazard ratio 1.63, 95% confidence interval 1.11 to 2.37), overweight participants without MetS (hazard ratio 1.52, 95% confidence interval 1.28 to 1.80), overweight participants with MetS (hazard ratio 1.74, 95% confidence interval 1.32 to 2.30), obese participants without MetS (hazard ratio 1.95, 95% confidence interval 1.14 to 3.34), and obese participants with MetS (hazard ratio 2.55, 95% confidence interval 1.81 to 3.58) compared with normal-weight individuals without MetS. These BMI-MetS categories significantly predicted total mortality rate in a similar pattern. Conclusions— Middle-aged men with MetS had increased risk for cardiovascular events and total death regardless of BMI status during more than 30 years of follow-up. In contrast to previous reports, overweight and obese individuals without MetS also had an increased risk. The present data refute the notion that overweight and obesity without MetS are benign conditions.